制定国家针对特定压力因素的属性敏感度值
1U.S. Environmental Protection Agency, Office of Research and Development, Center for Environmental Monitoring and Modelling, 26 Martin Luther King Drive West, Cincinnati, OH 45168, United States of America.
The Science of the total environment
|June 28, 2023
概括
超过700个属的新敏感值 (SV) 有助于估计敏感属比 (SGR) 以评估溪流健康. 这一指标有助于识别来自常见环境压力因素的生物损伤.
科学领域:
- 环境科学 环境科学
- 生态生态学 生态生态学
- 评估水质水质的评估.
背景情况:
- 有效的水质管理依赖于理解应激因子反应关系.
- 目前的评估受到水生生物缺乏预先确定的压力反应关系的限制.
- 发展这种关联对于准确的生物损伤评估至关重要.
研究的目的:
- 开发属性应激因子特定的敏感度值 (SVs),用于估计敏感属性比 (SGR) 度量.
- 创建一个工具来评估流中由常见的环境压力因素引起的生物损害.
- 为克服当前水质评估中的局限性提供一种方法.
主要方法:
- 使用来自连接美国的大型宏观无脊椎动物和环境数据集,估计了多达704个属的属性敏感度值 (SVs).
- 计算了一般和环境变量的相对丰度加权平均值 (WA),根据压力因子梯度分配 SV.
- 开发了敏感属比 (SGR),即 SV ≤ 5 的属数除以样本中属的总数.
主要成果:
- 敏感属比 (SGR) 总体上下降,因为环境压力在许多变量中增加.
- 对于29个环境变量中的23个,最不受到干扰的站点显示SGR平均值的95%置信区间比其他站点更大.
- 区域分析表明,SGR在美国东部和中部地区表现最好.
结论:
- 开发的压力特异性SV和SGR指标为评估流生物损害提供了有价值的新工具.
- 这种方法通过提供可量化的应激因子反应关联,提高了管理水质的能力.
- 这些发现支持生物评估方法在环境监测中的更广泛应用.
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